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PubMed · 7832068

[Accommodation function and its clinical evaluation].

Abstract

One subjective examination in accommodation, we found fundamental fault in the self-selection of clear vision against stimulus target and the time control of examination. On the other hand, it was difficult to objectively judge clear vision or check subjects consciousness for the tests. In this study, we made a trial instrument called new accommodometer which was able to confirm the time limit for clear vision, and measured response time for accommodation in constriction and relaxation. Young healthy subjects could obtain clear vision within 0.5 seconds on the new accommodometer, but this took over 0.8 seconds with scattered distribution on an accommodopolyrecorder. The required time for clear vision tended to increase in diabetic cases, and also in pseudophakia corrected bifocal lenses, over 0.6 seconds. We analyzed the form of accommodative response under clear vision, using on infrared optometer with stimulus-targets prepared outside, meanwhile changing the size of targets and amplitude of accommodative stimulus. When we compare these results to those of the new accommodometer, it will be easily seen that accommodative clear vision may be acquired in a rapid response stage after a latent period of constrictive accommodation, and usually with a steady running time under 4 D stimulus. For getting clear vision in far and near objects simultaneously, in pseudophakia, moderate astigmatism plays an important part, but it tends to cause deteriorated quality of clear vision. In diffractive intraocular lenses, we can find patients who are able to see using arbitrarily both areas, the refractive or diffractive part. We analyzed microfluctuation of accommodation by the maximum entropy method, and one of the typical cases revealed three-dimensional drawings reconstructed from it. In analyzing the spectral power of young healthy subjects, the response waves tend to increase in blurred conditions for targets.

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BibTeXRIS

K Kato. 1994. [Accommodation function and its clinical evaluation].. https://pubmed.ncbi.nlm.nih.gov/7832068/

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